Herbicidal phenylpyridines

Abstract

The present invention relates to phenylpyridines of formula (I) ##STR00001##
wherein the variables are defined according to the description, processes and intermediates for preparing the phenylpyridines of the formula (I), compositions comprising them and their use as herbicides, i.e. for controlling harmful plants, and also a method for controlling unwanted vegetation which comprises allowing a herbicidal effective amount of at least one phenylpyridine of the formula (I) to act on plants, their seed and/or their habitat.

Claims

1. A compound of formula (I) ##STR00021## wherein the variables have the following meanings: R.sup.1 halogen, C.sub.1-C.sub.4-haloalkyl or SO.sub.2CH.sub.3; R.sup.2 H, CH.sub.3 or NH.sub.2; R.sup.3 halogen; R.sup.4 H or halogen; R.sup.5 halogen or CN; R.sup.6 H or CH.sub.3; R.sup.7 C.sub.1-C.sub.6-alkoxy, C.sub.1-C.sub.6-haloalkoxy, C.sub.3-C.sub.6-alkenyloxy, or C.sub.3-C.sub.6-alkynyloxy; R.sup.8 OR.sup.9, SR.sup.9, NR.sup.10R.sup.11, NR.sup.9S(O)R.sup.10, NR.sup.9S(O).sub.2R.sup.10, NR.sup.9S(O)NR.sup.10R.sup.11, or NR.sup.9S(O).sub.2NR.sup.10R.sup.11, wherein R.sup.9 is hydrogen, C.sub.1-C.sub.6-alkyl, C.sub.3-C.sub.6-alkenyl, C.sub.3-C.sub.6-alkynyl, C.sub.1-C.sub.6-haloalkyl, C.sub.3-C.sub.6-haloalkenyl, C.sub.3-C.sub.6-haloalkynyl, C.sub.1-C.sub.6-cyanoalkyl, C.sub.1-C.sub.6-alkoxy-C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkoxy-C.sub.1-C.sub.6-alkoxy-C.sub.1-C.sub.6-alkyl, di(C.sub.1-C.sub.6-alkoxy)C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-haloalkoxy-C.sub.1-C.sub.6-alkyl, C.sub.3-C.sub.6-alkenyloxy-C.sub.1-C.sub.6-alkyl, C.sub.3-C.sub.6-haloalkenyloxy-C.sub.1-C.sub.6-alkyl, C.sub.3-C.sub.6-alkenyloxy-C.sub.1-C.sub.6-alkoxy-C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkylthio-C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkylsulfinyl-C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkylsulfonyl-C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkylcarbonyl-C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkoxycarbonyl-C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-haloalkoxycarbonyl-C.sub.1-C.sub.6-alkyl, C.sub.3-C.sub.6-alkenyloxycarbonyl-C.sub.1-C.sub.6-alkyl, amino, (C.sub.1-C.sub.6-alkyl)amino, di(C.sub.1-C.sub.6-alkyl)amino, (C.sub.1-C.sub.6-alkylcarbonyl)amino, amino-C.sub.1-C.sub.6-alkyl, (C.sub.1-C.sub.6-alkyl)amino-C.sub.1-C.sub.6-alkyl, di(C.sub.1-C.sub.6-alkyl)amino-C.sub.1-C.sub.6-alkyl, aminocarbonyl-C.sub.1-C.sub.6-alkyl, (C.sub.1-C.sub.6-alkyl)aminocarbonyl-C.sub.1-C.sub.6-alkyl, di(C.sub.1-C.sub.6-alkyl)aminocarbonyl-C.sub.1-C.sub.6-alkyl, NCR.sup.12R.sup.13, wherein R.sup.12 and R.sup.13 independently of one another are H, C.sub.1-C.sub.4-alkyl or phenyl; C.sub.3-C.sub.6-cycloalkyl, C.sub.3-C.sub.6-cycloalkyl-C.sub.1-C.sub.6-alkyl, C.sub.3-C.sub.6-heterocyclyl, C.sub.3-C.sub.6-heterocyclyl-C.sub.1-C.sub.6-alkyl, phenyl, phenyl-C.sub.1-C.sub.4-alkyl or a 5- or 6-membered heteroaryl, wherein each phenyl or heteroaryl ring can be substituted by one to four substituents selected from R.sup.14 or a 3- to 7-membered carbocycle, which carbocycle optionally has in addition to carbon atoms one or two ring members selected from the group consisting of N(R.sup.12), NN, C(O), O and S, and which carbocycle is optionally substituted with one to four substituents selected from R.sup.14; wherein R.sup.14 is halogen, NO.sub.2, CN, C.sub.1-C.sub.4-alkyl, C.sub.1-C.sub.4-haloalkyl, C.sub.1-C.sub.4-alkoxy or C.sub.1-C.sub.4-alkoxy-carbonyl; R.sup.10, R.sup.11 independently of one another are R.sup.9, or together form a 3- to 7-membered carbocycle, which carbocycle optionally has in addition to carbon atoms one or two ring members selected from the group consisting of N(R.sup.12), NN, C(O), O and S, and which carbocycle is optionally substituted with one to four substituents selected from R.sup.14; X O or S; and Y O or S; or an agriculturally acceptable salt thereof.

2. The compound of claim 1, wherein R.sup.1 is C.sub.1-C.sub.4-haloalkyl.

3. The compound of claim 1, wherein R.sup.2 is H.

4. The compound of claim 1, wherein R.sup.3 is F, Cl or Br.

5. The compound of claim 1, wherein R.sup.6 is H.

6. The compound of claim 1, wherein R.sup.7 is C.sub.1-C.sub.6-alkoxy or C.sub.1-C.sub.6-haloalkoxy.

7. The compound of claim 1, wherein R.sup.8 is OR.sup.9 or NR.sup.9S(O).sub.2R.sup.9.

8. The compound of claim 1, which corresponds to the formula (I.a) ##STR00022## wherein R.sup.3, R.sup.4, R.sup.7 and R.sup.8 are as defined in claim 1.

9. A process for the preparation of the compound of claim 1, wherein an acid chloride (II) ##STR00023## is reacted with a compound (III)
HR.sup.8(III), in the presence of a base, wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are as defined in claim 1.

10. A herbicidal composition comprising an herbicidally active amount of at least one phenylpyridine of formula (I) as claimed in claim 1 and at least one inert liquid and/or solid carrier and, if appropriate, at least one surface-active substance.

11. A process for the preparation of herbicidal active compositions, which comprises mixing an herbicidally active amount of at least one phenylpyridine of formula (I) as claimed in claim 1 and at least one inert liquid and/or solid carrier and, if desired, at least one surface-active substance.

12. A method of controlling undesired vegetation, which comprises allowing an herbicidally active amount of at least one compound of claim 1 to act on plants, their environment or on seed.

13. The method of claim 12, wherein R.sup.1 is C.sub.1-C.sub.4-haloalkyl.

14. The method of claim 12, wherein R.sup.2 is H.

15. The method of claim 12, wherein R.sup.3 is F Cl or Br.

16. The method of claim 12, wherein R.sup.6 is H.

17. The method of claim 12, wherein R.sup.7 is C.sub.1-C.sub.6-alkoxy or C.sub.1-C.sub.6-haloalkoxy.

18. The method of claim 12, wherein R.sup.8 is OR.sup.9 or NR.sup.9S(O).sub.2R.sup.9.

19. Acid chlorides of formula (II) ##STR00024## wherein the variables have the following meanings: R.sup.1 halogen, C.sub.1-C.sub.4-haloalkyl or SO.sub.2CH.sub.3; R.sup.2 H, CH.sub.3 or NH.sub.2; R.sup.3 halogen; R.sup.4 H or halogen; R.sup.5 halogen or CN; R.sup.6 H or CH.sub.3; R.sup.7 C.sub.1-C.sub.6-alkoxy, C.sub.1-C.sub.6-haloalkoxy, C.sub.3-C.sub.6-alkenyloxy, or C.sub.3-C.sub.6-alkynyloxy; X O or S; and Y O or S.

Description

A PREPARATION EXAMPLES

Example 1

Methyl 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-methoxy-acetate (I.a.200)

(1) ##STR00014##

(2) 1.5 g (4.60 mmol) 2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenol (CAS180153-43-9) was dissolved in 50 ml dimethylformamide, 1.91 g (13.8 mmol) K.sub.2CO.sub.3 was added and after stirring for 5 min at room temperature 1.68 g (9.20 mmol) methyl 2-chloro-2-methoxy-acetate (CAS 13157-96-5) dissolved in 5 ml DMF was added. The suspension was heated for 12 h to 50 C. After cooling the suspension was filtered, the filtrate washed with ethylacetate and the combined liquid phases evaporated. The residue was 1.17 g methyl 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-methoxy-acetate as a colorless oil.

(3) .sup.1H-NMR (d.sup.6-DMSO, ppm): 9.1 (s, 1H); 8.7 (s, 1H); 7.8 (d, 1H); 7.5 (d, 1H); 5.9 (s, 1H); 3.8 (s, 3H); 3.6 (s, 3H).

(4) m/z=428.1; Rt=1.332 min

Example 2

2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-ethoxy-acetic acid (I.a.232)

(5) ##STR00015##

(6) 300 mg (0.66 mmol) ethyl 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-ethoxy-acetate, dissolved in 3 ml tetrahydrofurane, was added to 79 mg (3.3 mmol) lithium hydroxide in 3 ml water. The solution was stirred for 12 h at room temperature. The solvents were evaporated and the residue dissolved in water. The aqueous phase was acidified with 1N HCl and extracted with dichloromethane. The organic phase was evaporated resulting in 281 mg 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-ethoxy-acetic acid as colorless oil.

(7) .sup.1H-NMR (d.sup.6-DMSO, ppm): 9.1 (s, 1H); 8.7 (s, 1H); 7.6 (d, 1H); 7.3 (d, 1H); 5.1 (s, 1H); 3.8 (m, 1H); 3.6 (m, 1H); 1.1 (t, 3H).

(8) m/z=429.5; Rt=1.218 min

Example 3

Ethyl 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-ethoxy-acetate (I.a.234)

(9) ##STR00016##

(10) 1.0 g (3.07 mmol) 2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenol (CAS 180153-43-9) was dissolved in 35 ml dimethylformamide, 1.27 g (9.20 mmol) K.sub.2CO.sub.3 was added and after stirring for 5 min at room temperature 1.02 g (6.12 mmol) ethyl 2-chloro-2-ethoxy-acetate (CAS 34006-60-5) dissolved in 5 ml dimethylformamide was added. The suspension was heated for 12 h to 50 C. After cooling the suspension was filtered, the filtrate washed with ethylacetate and the combined organic phases evaporated. The residue was 1.17 g ethyl 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-ethoxy-acetate as a colorless oil.

(11) .sup.1H-NMR (d.sup.6-DMSO, ppm): 9.1 (s, 1H); 8.7 (s, 1H); 7.7 (d, 1H); 7.4 (d, 1H); 5.9 (s, 1H); 4.2 (q, 2H); 3.8 (m, 2H); 1.2 (m, 6H).

(12) m/z=456.6; Rt=1.421 min

Example 4

2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-ethoxy-N-methylsulfonyl-acetamide (I.a.261)

(13) ##STR00017##

(14) 81 mg (0.19 mmol) 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-ethoxy-acetic acid was dissolved in 3 ml tetrahydrofurane. 62 mg (0.38 mmol) 1,1-carbonyldiimidazole was added and the solution heated to reflux for 1 h. After cooling 35 mg (0.38 mmol) methanesulfonamide and 58 mg (0.38 mmol) diazabicycloundecene was added and the solution was stirred for 12 h at room temperature. The solution was added to 10% aqueous HCl and extracted with methyl-tert-butylether. The organic phase was evaporated resulting in 80 mg 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-ethoxy-N-methylsulfonyl-acetamide 5 as colorless oil.

(15) .sup.1H-NMR (d.sup.6-DMSO, ppm): 9.1 (s, 1H); 8.7 (s, 1H); 7.8 (d, 1H); 7.3 (d, 1H); 6.8 (s, 1H); 5.1 (s, 1H); 3.8 (m, 1H); 3.6 (m, 1H); 2.5 (s, 3H); 1.1 (m, 3H).

(16) m/z=506.5; Rt=1.203 min

Example 5

Methyl 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-methylsulfanyl-acetate

(17) ##STR00018##

(18) 300 mg (0.92 mmol) 2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenol (CAS180153-43-9) was dissolved in 10 ml dimethylformamide, 267 mg (1.92 mmol) K.sub.2CO.sub.3 was added and after stirring for 5 min at room temperature 320 mg (1.61 mmol) methyl 2-chloro-2-thiomethoxy-acetate (CAS 62383-81-7) dissolved in 5 ml DMF was added. The suspension was heated for 12 h to 50 C. After cooling the suspension was filtered, the filtrate washed with ethylacetate and the combined liquid phases evaporated. The residue was 410 mg methyl 2-[2-chloro-5-[3-chloro-5-(trifluoromethyl)-2-pyridyl]-4-fluoro-phenoxy]-2-methylsulfanyl-acetate as a colorless oil.

(19) .sup.1H-NMR (d.sup.6-DMSO, ppm): 8.9 (s, 1H); 8.1 (s, 1H); 7.4 (d, 1H); 7.2 (d, 1H); 5.6 (s, 1H); 3.9 (s, 3H); 2.3 (s, 3H).

(20) m/z=443.9; Rt=1.372 min

(21) The compounds listed below in table 2 can be prepared similarly to the examples mentioned above:

(22) ##STR00019## (I), wherein R.sup.2 is H, R.sup.5 is Cl, R.sup.6 is H and Y is O

(23) TABLE-US-00006 TABLE 2 Ex R.sup.1 R.sup.3 R.sup.4 R.sup.7 R.sup.8 X m/z R.sub.t [min] 6 Cl Cl H OCH.sub.3 OCH.sub.3 O 377.7 1.296 7 CHF.sub.2 Cl F OCH.sub.3 OCH.sub.3 O 409.3 1.348 8 CF.sub.3 F F OCH.sub.3 OCH.sub.3 O 411.1 1.212 9 CF.sub.3 F F OCH.sub.3 NHSO.sub.2CH.sub.3 O 474.1 1.117 10 CF.sub.3 Cl H OCH.sub.3 OCH.sub.3 O 409.7 1.318 11 CF.sub.3 Cl F OCH.sub.3 OH O 413.8 1.17 12 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH.sub.3 O 441.8 1.358 13 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH.sub.2CH.sub.3 O 455.9 1.404 14 CF.sub.3 Cl F OCH.sub.3 OCH(CH.sub.2CH.sub.3).sub.2 O 483.8 1.491 15 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2C(CH.sub.3)CH.sub.2 O 467.8 1.418 16 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CHCH.sub.2 O 453.9 1.374 17 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CCH O 451.9 1.328 18 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CCCH.sub.3 O 465.9 1.355 19 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH.sub.2CH.sub.2CCH O 481.3 1.415 20 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CHF.sub.2 O 477.8 1.334 21 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH.sub.2Cl O 475.7 1.35 22 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CHCl.sub.2 O 511.8 1.401 23 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH.sub.2OCH.sub.3 O 471.8 1.312 24 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH.sub.2CH.sub.2OCH.sub.3 O 485.9 1.325 25 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH.sub.2OCH.sub.2CH.sub.3 O 485.9 1.364 26 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH.sub.2OCH(CH.sub.3).sub.2 O 500 1.409 27 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH(OCH.sub.3).sub.2 O 469.8 1.323 28 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH(OCH.sub.2CH.sub.3).sub.2 O 483.9 1.408 29 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2COOCH.sub.3 O 485.8 1.228 30 CF.sub.3 Cl F OCH.sub.3 OCH(CH.sub.3)COOCH.sub.3 O 499.9 1.331 31 CF.sub.3 Cl F OCH.sub.3 Oc-C.sub.4H.sub.7 O 467.9 1.425 32 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2c-C.sub.3H.sub.5 O 467.9 1.401 33 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2c-C.sub.4H.sub.7 O 481.9 1.453 34 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2-(2-furyl) O 493.8 1.373 35 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2C.sub.6H.sub.5 O 503.9 1.42 36 CF.sub.3 Cl F OCH.sub.3 O[(2-OCH.sub.2CH.sub.3)C.sub.6H.sub.4] O 533.6 1.413 37 CF.sub.3 Cl F OCH.sub.3 OCH.sub.3 S 443.9 1.349 38 CF.sub.3 Cl F OCH.sub.3 NHCH.sub.3 O 90 1.18 39 CF.sub.3 Cl F OCH.sub.3 NHCH.sub.2CCH O 450.8 1.224 40 CF.sub.3 Cl F OCH.sub.3 NHSO.sub.2CH.sub.3 O 491.1 1.207 41 CF.sub.3 Cl F OCH.sub.3 NHSO.sub.2N(CH.sub.3)(CH(CH.sub.2).sub.2) O 547.9 1.313 42 CF.sub.3 Cl F SCH.sub.3 OCH.sub.3 S 460 1.441 43 CF.sub.3 Cl F OCH.sub.3 NCH.sub.2[(3-OCH.sub.3)C.sub.6H.sub.4] O 533 1.332 44 CF.sub.3 Cl F OCH.sub.3 NCH.sub.2[(4-OCH.sub.3)C.sub.6H.sub.4] O 533 1.327 45 CF.sub.3 Cl F OCH.sub.3 NCH.sub.2C.sub.6H.sub.5 O 503 1.337 46 CF.sub.3 Cl F OCH.sub.3 NCH.sub.2CH.sub.2CH.sub.2OCH.sub.3 O 485 1.242 47 CF.sub.3 Cl F OCH.sub.3 NCH.sub.2CH.sub.2OCH.sub.3 O 471 1.219 48 CF.sub.3 Cl F OCH.sub.3 NCH.sub.2c-C.sub.3H.sub.5 O 467 1.301 49 CF.sub.3 Cl F OCH.sub.3 NCH.sub.2CHCH.sub.2 O 453 1.264 50 CF.sub.3 Cl F OCH.sub.3 NCH.sub.2CH.sub.3 O 441 1.237 51 CF.sub.3 Cl F OCH.sub.3 N(CH.sub.3)CH.sub.2CN O 465.9 1.224 52 CF.sub.3 Cl F OCH.sub.3 2,5-dihydropyrrol-1-yl O 465 1.265 53 CF.sub.3 Cl F OCH.sub.3 N(CH.sub.3)CH(CH.sub.3).sub.2 O 469 1.329 54 CF.sub.3 Cl F OCH.sub.3 N(CH.sub.3)CH.sub.2CHCH.sub.2 O 467 1.312 55 CF.sub.3 Cl F OCH.sub.3 N(CH.sub.3)CH.sub.2CH.sub.2CH.sub.3 O 469 1.334 56 CF.sub.3 Cl F OCH.sub.3 N(CH.sub.3)CH.sub.2CCH O 465 1.274 57 CF.sub.3 Cl F OCH.sub.3 N(CH.sub.3)CH.sub.2CH.sub.2OCH.sub.3 O 485 1.253 58 CF.sub.3 Cl F OCH.sub.3 thiomorpholine O 498.9 1.322 59 CF.sub.3 Cl F OCH.sub.3 1-piperidyl O 481 1.356 60 CF.sub.3 Cl F OCH.sub.3 O(tetrahydropyran-4-yl) O 498 1.319 61 CF.sub.3 Cl F OCH.sub.3 Oc-C.sub.3H.sub.5 O 453.9 1.357 62 CF.sub.3 Cl F OCH.sub.3 Oc-C.sub.6H.sub.11 O 496 1.5 63 CF.sub.3 Cl F OCH.sub.3 Oc-C.sub.5H.sub.9 O 481.9 1.453 64 CF.sub.3 Cl F OCH.sub.3 OCH(CH.sub.3).sub.2 O 456 1.389 65 CF.sub.3 Cl F OCH.sub.3 NH.sub.2 O 412.9 1.133 66 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2COOCH(CH.sub.3).sub.2 O 514 1.399 67 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2COOCH.sub.2CH.sub.3 O 500 1.358 68 CF.sub.3 Cl F OCH.sub.3 OCH.sub.2CH(CH.sub.3).sub.2 O 470.1 1.466 69 CF.sub.3 Cl F OCH.sub.3 morpholino O 483 1.224 70 CF.sub.3 Cl F OCH.sub.3 pyrrolidin-1-yl O 467 1.272 71 CF.sub.3 Cl F OCH.sub.3 azetidin-1-yl O 453 1.228 72 CF.sub.3 Cl F OCH.sub.3 N(CH.sub.3).sub.2 O 441 1.229 73 CF.sub.3 Cl F OCH.sub.3 1-methyl-4-piperidyl O 511 1.009 74 CF.sub.3 Cl F OCH.sub.3 O(oxetan-3-yl) O 469.9 1.259

(24) The compounds listed below in table 3 can be prepared similarly to the examples mentioned above:

(25) ##STR00020## (I), wherein R.sup.2 is H, R.sup.5 is CN, R.sup.6 is H and Y is O

(26) TABLE-US-00007 TABLE 3 Ex R.sup.1 R.sup.3 R.sup.4 R.sup.7 R.sup.8 X m/z R.sub.t [min] 75 CF.sub.3 Cl F OCH.sub.3 OCH.sub.3 O 418.9 1.231 76 CF.sub.3 Cl F OCH.sub.3 OH O 404.6 1.114

B USE EXAMPLES

(27) The herbicidal activity of the phenylpyridines of formula (I) was demonstrated by the following greenhouse experiments:

(28) The culture containers used were plastic flowerpots containing loamy sand with approximately 3.0% of humus as the substrate. The seeds of the test plants were sown separately for each species.

(29) For the pre-emergence treatment, the active ingredients, which had been suspended or emulsified in water, were applied directly after sowing by means of finely distributing nozzles. The containers were irrigated gently to promote germination and growth and subsequently covered with transparent plastic hoods until the plants had rooted. This cover caused uniform germination of the test plants, unless this had been impaired by the active ingredients.

(30) For the post-emergence treatment, the test plants were first grown to a height of 3 to 15 cm, depending on the plant habit, and only then treated with the active ingredients which had been suspended or emulsified in water. For this purpose, the test plants were either sown directly and grown in the same containers, or they were first grown separately as seedlings and transplanted into the test containers a few days prior to treatment.

(31) Depending on the species, the plants were kept at 10-25 C. or 20-35 C., respectively.

(32) The test period extended over 2 to 4 weeks. During this time, the plants were tended, and their response to the individual treatments was evaluated.

(33) Evaluation was carried out using a scale from 0 to 100. 100 means no emergence of the plants, or complete destruction of at least the aerial moieties, and 0 means no damage, or normal course of growth. A good herbicidal activity is given at values of at least 70 and a very good herbicidal activity is given at values of at least 85.

(34) The plants used in the greenhouse experiments were of the following species:

(35) TABLE-US-00008 Bayer code Scientific name AMARE Amaranthus retroflexus CHEAL Chenopodium album SETVI Setaria viridis

(36) At an application rate of 16 g/ha, example 6, applied by the post-emergence method, showed very good herbicidal activity against Amaranthus retroflexus and Setaria viridis, and good herbicidal activity against Chenopodium album.

(37) At an application rate of 16 g/ha, examples 1, 2, 3, 4, 7, 8, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 38, 39, 40 and 41 applied by the post-emergence method, showed very good herbicidal activity against Amaranthus retroflexus, Chenopodium album and Setaria viridis.

(38) At an application rate of 16 g/ha, example 44, applied by the post-emergence method, showed very good herbicidal activity against Amaranthus retroflexus and Chenopodium album, and good herbicidal activity against Setaria viridis.

(39) At an application rate of 16 g/ha, examples 43, 45, 46, 47, 48, 49, 50, 56, 57, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 72, 73, 74 and 75 applied by the post-emergence method, showed very good herbicidal activity against Amaranthus retroflexus, Chenopodium album and Setaria viridis.

(40) At an application rate of 16 g/ha, examples 51, 52, 53, 54, 55, 58, 69, 70 and 71 applied by the post-emergence method, showed very good herbicidal activity against Amaranthus retroflexus and Chenopodium album.